Antifriction mechanism for lifting-jacks



F. L. GORMLEY.

ANTIFRICTION MECHANISM FOR LIFTING J ACKS. APPLlCATION- FILED JAN.20, 192x.

1,381,988 v PatentedJune 21,1921.

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PATENT OFFHQE.

FRANK I1. G-ORMLEY, OF BROOKLINE, MASSACHUSETTS.

'ANTIFRIGTIGN MECHANISM FOR LIFTI'NG-JAGKS.

Specification of Letters Patent.

Patented June 21, 1921.

Application filed January 20, 1921. Serial No. 438,539.

To all w ham "it may concern Be it known that I, FRANK L. GonMLnY, a citizen of the United States of America, and a resident of Brookline, in the county of Norfolk and Commonwealth of Massachusetts, have invented certain new and useful Improvements in Antifriction Mechanism for Lifting-Jacks, of which the following is a specification.

This invention relates to lifting jacks and particularly to devices of this character known as screw jacks in which a movable member is moved endwise of a standard on a supporting base.

In the use of these devices it often be comes necessary to actuate them while in an angular position and under such conditions there is liable to be a cramping between the movable member and the standard lengthwise of which said member is to be moved.

This cramping produces an undue amount of friction which is very objectionable and the principal purpose of the present inven tion is to overcome this objection by producing a jack in which all friction between the movable member and the standard is effectually eliminated.

The invention consists in providing the movable member with a plurality of rollers which surround the standard and coact therewith.

The invention further consists in certain novel features of construction and arrangement of parts which will be understood readily by reference to the description of the drawings and to the claims to be hereinafter given.

For the purpose of illustrating the invention, one preferred form thereof is illustrated in the drawings, this form'having been found to give satisfactory and reliable results although it is to be understood that the various instrumentalities of which the invention consists can be variously arranged and organized and the invention is not limited to the precise arrangement and organization of these instrumentalities as herein shown and described except as required by the scope of the appended claims.

Of the drawings:

Figure 1 represents a horizontal section of a portion of a lifting jack embodying the principles of the present invention, and

Fig. 2 represents an elevation of the same, a portion being broken in section.

Similar characters indicate like parts throughout the several figures of the drawings.

In the drawings, 10 represents a standard pro ecting upwardly from the base of a screw lifting jack such as shown and descrlbedin Letters Patent No. 1,824,345 issued to me Dec. 9, 1919.

In the top of the standard 10 is mounted a non-revoluble nut 11 through which extends a revoluble lifting screw 12.

Surrounding the standard 10 and movable endwise thereof with. the screw 12 is a sleeve 13.

Ordinarily in lifting jacks of this construction it is often necessary to incline the jack in performing thework and when the jack is thus inclined the sleeve is liable to be tipped at an angle to the standard on which it is moving and become cramped thus making it very difficult to operate the ack.

To obviate this cramping of the movable sleeve upon the fixed standard 11, the sleeve 13 is provided with a plurality of lateral projections 14: in a plurality of planes perpendicular to the axis of the standard 10.

These projections are rectangularly disposed relatively to each other as indicated in Fig. 1 of the drawings.

Each'projection 141: is provided with a cylindrical chamber 15 in the inner end of which is mounted a bushing 16 having a bearing therein for the trunnion 17 on the end of a roller 18 disposed within said chamber 15.

The opposite end of the roller 18 is pro- ,vided with a trunnion 19 having a bearing in a bushing 20 threaded into the outer end of the chamber 15.

This bushing 20 is provided with a slot 21 by whichsaid bushing may be turned to remove it from the chamber 15 and permit the removal of the rollers 18 when it is desired to repair or renew the same.

These rollers have a peripheral surface curvedto fit the periphery of the standard 10 which extends into one side of all of said chambers and being disposed on all sides of said standard, the cramping of the movable member upon the standard 10 is prevented no matter which way the lifting jack may be tipped during the lifting operation.

The rollers 18 at opposite ends are provided with peripheral bearing surfaces 22 which rotate in contact with the walls of said chambers 14L and take up a great part of the strain brought to bear upon the rollers thereof and to reduce the frictional contact between the curved peripheral surface of these rollers and the cylindrical surface of the standard 10. V

This is a very simple device for overcoming friction between themovable sleeve and the standard of a lifting ack when the ack is inclined but at the same time it is most effective in itsoperation and the results attained.

It is believed that the operation and many advantages of the invention will be understood without further description.

- Having thus described my invention, I claim 1. In a lifting jack, a fixed cylindrical standard; a member movable thereon; and anti-friction members on said movable member and oppositely disposed coasting with the wall of said standard 2. In a lifting jack, a fixed cylindrical standard; a member movable thereon; and rollers on said movable member and oppositely disposed coacting with th wall of said standard.

8. In a lifting jack a fixed cylindrical standard; a member movable thereon; and rollers on said movable member and oppositelv disposed having peripheral surfaces fittted to and coacting with the wall of said sta ndard.

4:. In a lifting jack, a fixed standard; a member movable thereon having a plurality of chambers in the walls thereof open to ward the center of said member; bushings in sald chambers; and rollers 1n sa1d chambers havmg trunmons revolubly mounted 1n said bushings, said rollers having peripheral surfaces coacting with the wall of said standard.

5. In a lifting jack, a fixed standard; a member movable thereon having a plurality of chambers in the walls thereof open toward the center of said member; bushings in said chambers; and rollers in said chambers having trunnions revolubly mounted in I said bushings said rollers having peripheral surfaces fitted to and coacting with the wall of said standard.

6. In a lifting jack, a fixed standard; a member movable thereon having a plurality of chambers in the walls thereof open toward the center of said member and disposed in rectangular relation to each other; bushings in said chambers; and rollers in said chambers having trunnions revolubly mounted in said bushings said rollers having peripheral surfaces coasting with the wall of said standard.

7. In a lifting jack, a fixed standard; a member movable thereon having a plurality of chambers in the walls thereof opentoward the center of said member and disposed in rectangular relation to each other in two parallel planes perpendicular to the axis of said standard; bushings in said chambers;

and rollers in said chambers having trunnions revolubly mounted in'said bushings said rollers having peripheral surfaces coacting with the wall of said standard.

8. Ina lifting jack, afiXed standard; a member movable thereon having a plurality of chambers in the walls thereof open toward the center of said member; two bushings in each. of said chambers, 'one'of which is threaded and removable; and rollers in said chambers having trunnions revolubly mounted in said bushings, said rollers having peripheral surfaces coacting with the Wall of said standard.

Signed by me at 294 Washington St, Boston, Mass, this 18th day of January, 1921. FRANK L. GORNELEY.

' Witnesses:

WALTER E. LOMBARD,

V NATHAN C. LOMBARD. 

